1. The problem statement, all variables and given/known data The potential energy of a system consisting of two identical charges is 4.5 mJ when their separation is 38 mm. a) What is the magnitude of each charge? b) How many individual charges are present in the system? (You can assume the charges are either electrons or protons.) 2. Relevant equations F=Ke(q1*q2)/r^2 3. The attempt at a solution I'm not really sure where to start. Do I need the charge of an electron or proton? Any help would be awesome!